>> Certificate verification failed: The certificate is NOT trusted. The 
>> certificate chain uses expired certificate.  Could not handshake: Error 
>> in the certificate verification. [IP: 95.216.163.36 443] 
>> 
> Maybe renew the key ?
The repo uses a LetsEncrypt certificate. 
Odds are, the OP's system's trust store is quite old and so still has the old root in place - LE's intermediate has multiple signatures and one of the roots expired last year.
Running
    sudo apt-get -y install ca-certificates
Should bring it up to date (assuming there's a relatively modern openssl in use - I think 1.0 will throw an error either way because it still tries to follow both forks in the chain and borks when it sees the expired cert).